WASHINGTON (CNN) -- Republican presidential hopeful Fred Thompson Monday said he didn't need to apologize for his faith, despite concerns from Christian conservatives that he does not express his religious beliefs enough on the campaign trail.

Fred Thompson says his campaign is in a strong position one month before the Iowa caucuses.

"As far as faith is concerned, I have not made any secret as to where I am. I am a Christian," Thompson said, noting that, while he does not attend church while at home in McLean, Virginia, he does attend church with his mother when he visits in Tennessee. "I have no apologies to make about my religion or my relationship to Jesus Christ or God."

In a column in USA Today Monday, David Domke, a University of Washington journalism professor, said Thompson has not done better in the polls because "he lacks a religious niche" and "Christian conservatives have not been amused or enthused" by his lack of church attendance and the few times he has talked of his faith on the campaign trail.

Thompson also said his campaign is in a strong position one month before the Iowa caucus and downplayed polls suggesting he may be losing support in crucial early voting states.

"I've been running consistently second in the nationwide polls," the former Tennessee senator said. "I've been running pretty consistently close in South Carolina, so our campaign is where we need to be."

In an interview, Thompson dismissed recent surveys out of Iowa and New Hampshire that suggest he has slipped significantly behind the front-runners.

"I think a lot of people expected me to blow a lot of people away when I got in the race. I knew better than that and of course it hasn't happened," Thompson said.

A Des Moines Register poll released Sunday showed Thompson in fourth place in Iowa with 9 percent of the vote, a 9 percentage point decrease from a similar survey in October. The poll, conducted November 25-28, had a margin of error of plus or minus 4.4 percentage points.

Meanwhile, a Fox News/Opinion Dynamic poll out of New Hampshire conducted November 27-29 puts Thompson at 4 percent there. The poll's margin of error was plus or minus 4 percentage points.

Thompson said his support is considerably strong in South Carolina -- the first southern state to weigh in at the polls on January 19 -- and he dismissed a recent American Research Group poll there showing him in fourth place with 13 percent.

"That is the most outlying thing I've ever heard," he said. "I don't even know who those people are."

"You have these things that come out about every 48 hours now. I can't answer for all of them," he said. "All I can tell you is that in South Carolina as well as in other parts of the country from Texas and out into California, where I was this weekend, I am doing very well."E-mail to a friend